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Inflammatory bowel disease (IBD) is a multifactorial chronic disease, commonly associated with alteration in the composition and function of gut microbiota. This process can lead to a decreased production of short chain fatty acids (SCFAs) by the gut microbiota, mainly butyrate, which is an important immunomodulatory molecule in the intestine. Butyrogenic bacteria normally produces butyrate through carbohydrate fermentation or amino acids degradation pathways. This molecule plays an important protective role in intestinal homeostasis acting in both adaptive immunity and innate immunity. This review summarizes the current knowledge about the role of butyrate on the development of IBD and the protective mechanisms of this metabolite on the intestinal mucosa and the whole body, as reported by in vitro and in vivo studies. Thus, butyrate can regulate the activation of regulatory T cells, increasing the acetylation of histones and decreasing the activation of NF-κB. In addition, it can also stimulate the mucus production from epithelial cells and the rearrangement of tight junction proteins.

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RESUMEN Introducción: Tradicionalmente, Rhodnius prolixus ha sido considerado el principal vector, mientras que Triatoma maculata resulta ser un vector secundario de Trypanosoma cruzi en el medio rural venezolano. En este trabajo se provee información de interés acerca de los componentes bioquímicos y del sistema inmune, humoral y celular, de la hemolinfa de R. prolixus y T. maculata alimentados sobre gallina y rata. Metodología: los insectos provenían de una colonia del laboratorio, mantenida a una temperatura de 27-29ºC, 50% de humedad relativa y ocho horas luz/día. Se analizó la hemolinfa de adultos alimentados sobre gallina y rata. Se observaron los hemocitos mediante microscopía óptica y electrónica de transmisión. Resultados: los parámetros bioquímicos de glucosa, lípidos y proteínas fueron afectados de forma distinta en R. prolixus y T. maculata según la fuente alimenticia. T. maculata presentó mayores niveles de actividad lítica de lisozima. Se observaron cuatro poblaciones de hemocitos (prohemocitos, plasmatocitos, granulocitos y oenocitos), cuyas características y medidas están acorde a lo reportado por otros autores sobre la subfamilia Triatominae. T. maculata presentó mayor número de prohemocitos y oenocitos que R. prolixus. Conclusiones: En su hemolinfa, R. prolixus y T. maculata son afectados distintamente en los componentes bioquímicos (glucosa, lípidos y proteínas) e inmunes, tanto humorales (lizosima) como celulares (prohemocitos, oenocitos), según sean alimentados sobre gallina y rata. Esto pone de manifiesto de la alimentación sobre uno de los componentes de la competencia vectorial, como lo es el sistema inmune propio de la hemolinfa de los insectos.

ABSTRACT Introduction: Traditionally, Rhodnius prolixus has been considered the main vector, while Triatoma maculata remains to be a secondary vector of Trypanosoma cruzi in the Venezuelan rural habitat. In this work, interesting information about the biochemical and immune (humoral and cellular) aspects of the hemolymph of R. prolixus and T. maculate, feeding on hen and rat, are presented. Methodology: Hemolymph was extracted from adult insects, maintained at 2729 °C with 50% of relative humidity and 8/16 (Light/Dark) hours, and fed on hen and rat. Hemocytes were observed by optical and transmission electron microscopy. Results: Biochemical parameters (glucose, lipids and proteins) varied in both species according to the food source. T. maculata presented higher levels of lysozyme lytic activity. Four hemocytes populations were observed by optical and transmission electron microscopy (prohemocytes, plasmocytes, granulocytes and oenocytes), exhibiting characteristics and measurements in accordance with previous literature related to the Triatominae subfamily. T maculata presented more prohemocytes and oenocytes than R. prolixus. Conclusions: On their hemolymph, R. prolixus and T. maculata are distinctly affected in their biochemical (glucose, lipids and proteins) and immune components, both humoral (lysozyme) and cellular (prohemocytes, oenocytes), depending on whether they were fed on hens or rats. Our results show that the food source affects the immune system of triatomines, and subsequently, their vectorial capacity may be compromised as well.

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Abstract Larvae and adults of certain species of predator lady beetles feed on pollen, guaranteeing their survival, and at times, reproduction in the absence of preferred prey. Palynology, therefore, may contribute in the investigation of botanical families visited by these predators in order to obtain this floral resource. There are records of the visitation of Apiaceae flowers by Coleomegilla maculata DeGeer, 1775 (Coleoptera, Coccinellidae), but not the ingestion of their pollen grains by this lady beetle. The external morphology of pollen grains of three Apiaceae aromatic species (Anethum graveolens L., Coriandrum sativum L., Foeniculum vulgare Mill.) was characterized, and it was evaluated the ingestion of these pollens by fourth instar larvae and adults of C. maculata upon confinement along with flowers of these Apiaceae for 24 and 48 hours. The pollen grains of those species presented similar external morphology. In the two times of exposure, the larvae ingested the same amount of pollen from the three Apiaceae species, and the amount of C. sativum pollen ingested was the same between larvae and adults. The amount of A. graveolens pollen grains ingested by the adults was significantly greater than the pollens of C. sativum and F. vulgare, in 24 hours, with the opposite occurring in 48 hours. In the first 24 hours, the adults ingested more A. graveolens pollen than the larvae, with the opposite occurring with F. vulgare. There was no significant difference in the amount of Apiaceae pollen ingested between larvae and adults in 48 hours. The results suggest that the pollen-eating habits of certain aphidophagous lady beetles may be crucial in their preservation within agro-ecosystems.

Resumo Larvas e adultos de certas espécies de joaninhas predadoras podem se alimentar de pólen, garantindo a sua sobrevivência, e, às vezes, a reprodução na ausência da presa preferencial. Palinologia, portanto, pode contribuir na investigação de famílias botânicas visitadas por estes predadores a fim de obter esse recurso floral. Há registros da visitação de flores de Apiaceae por Coleomegilla maculata DeGeer, 1775 (Coleoptera, Coccinellidae), mas não da ingestão de seus grãos de pólen por essa joaninha. A morfologia externa de grãos de pólen de três espécies aromáticas de Apiaceae (Anethum graveolens L., Coriandrum sativum L., Foeniculum vulgare Mill.) foi caracterizada e avaliou-se a ingestão desses polens por larvas de quarto instar e adultos de C. maculata em confinamento com flores dessas Apiaceae por 24 e 48 horas. Os grãos de pólen dessas espécies apresentaram morfologia externa semelhante. Nos dois tempos de exposição, as larvas ingeriram a mesma quantidade de pólen das três espécies de Apiaceae, e a quantidade de pólen de C. sativum ingerida foi semelhante entre as larvas e adultos. A quantidade de grãos de pólen de A. graveolens ingerida pelos adultos foi significativamente maior do que a dos polens de C. sativum e F. vulgare, em 24 horas, com o oposto ocorrendo em 48 horas. Nas primeiras 24 horas, os adultos ingeriram mais pólen de A. graveolens do que as larvas, ocorrendo o oposto com F. vulgare. Não houve diferença significativa na quantidade de pólen de Apiaceae ingerida entre as larvas e adultos em 48 horas. Os resultados sugerem que o hábito de alimentar de pólen de certas joaninhas afidófagas pode ser crucial para a sua preservação dentro dos agroecossistemas.

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In the aim to design a shielding for a 0.185 TBq (239)PuBe isotopic neutron source several Monte Carlo calculations were carried out using MCNP5 code. First, a point-like source was modeled in vacuum and the neutron spectrum and ambient dose equivalent were calculated at several distances ranging from 5 cm up to 150 cm, these calculations were repeated modeling a real source, including air, and a 1×1×1 m(3) enclosure with 5, 15, 20, 25, 30, 50 and 80 cm-thick Portland type concrete walls. At all the points located inside the enclosure neutron spectra from 10(-8) up to 0.5 MeV were the same regardless the distance from the source showing the room-return effect in the enclosure, for energies larger than 0.5 MeV neutron spectra are diminished as the distance increases. Outside the enclosure it was noticed that neutron spectra becomes "softer" as the concrete thickness increases due to reduction of mean neutron energy. With the ambient dose values the attenuation curve in terms of concrete thickness was calculated.

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Aplicar las recomendaciones terapéuticas establecidas por la Sociedad Venezolana de Infectología y observar los efectos en pacientes pediátricos con neumonía adquirida en la comunidad. Departamento de Pediatría. Servicio Autónomo del Hospital Central de Maracay. Estudio prospectivo, exploratorio. Las recomendaciones fueron aplicadas a 71 pacientes pediátricos con neumonía adquirida en la comunidad ingresados durante julio 2001-enero 2002, analizando al ingreso las variables: edad, sexo, Rx. de tórax, hemocultivo, Phadebact® de orina; y al ingreso más al tercer día: temperatura, frecuencia respiratoria, tiraje, vómitos, hematología completa y velocidad de sedimentación globular. Tratados: Penicilina Cristlina 250.000-400.000 U/kg/día. Se excluyeron aquellos que recibieron antimicrobianos diferentes a amoxicilina durante las primeras 72 horas previas al ingreso y los primeros días de hospitalización o con neumonías complicadas. Los Datos fueron recopilados en fichas, llevados a una base de datos, tabulados y analizados porcentualmente. La mayor frecuencia correspondió a menores de 6 años. El sexo más afectado: masculino 3:1. Clínica al ingreso: Taquipnea: 64,79 por ciento, tiraje 61,97 por ciento, fiebre 47,07 por ciento e intolerncia a la vía oral 15,49 por ciento. Reactantes de la fase aguda. Leucocitosis 100 por ciento, neutrofilia 70 por ciento y velocidad de sedimentación globular incrementada en partes. Después de 72 horas los resultados son positivos ante la práctica de esta conducta evidenciándose mejoría. Hemocultivos reportaron 100 por ciento negatividad, de 14 Phadebact® de orina positivos, el germen más frecuente: Streptococcus pneumoniae 57,14 por ciento con sensibilidad a la penicilina igualmente que Nesseria meningitides, siendo Haemophilus influenzae resistente. Radiológicamente la localización segmentaria estuvo en más del 50 por ciento. Estancia hospitalaria media: 4,74. Penicilina cristalina como tratamiento de elección establecido.

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In this work we investigate the antioxidant properties of an aqueous extract prepared from an infusion of Ilex paraguariensis (Aquifoliaceae) using free radical-generating systems. The extract inhibited the enzymatic and nonenzymatic lipid peroxidation in rat liver microsomes in a concentration-dependent fashion, with IC(50) values of 18 microg/ml and 28 microg/ml, respectively. The extract also inhibited the H(2)O(2)-induced peroxidation of red blood cell membranes with an IC(50) of 100 microg/ml and exhibited radical scavenging properties toward superoxide anion (IC(50) = 15 microg/ml) and 2,2-diphenyl-1-picrylhydrazyl radical. In the range of concentrations used, the extract was not a scavenger of the hydroxyl radical. Our results suggest that ingestion of extracts of Ilex paraguariensis could contribute to increase the antioxidant defense of an organism against free radicals attack.

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Se demostró con frecuencia la presencia de potenciales tardíos en el electrocardiograma de señales promediadas en 38 individuos con infección chagásica procedentes de una zona endémica del país, sero-positivos y asintomáticos, sin evidencia de enfermedad cardíaca

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